Vibrator.



W. LEWIS.

VIBRATOR;

APPLICATION FILED JUNE 10, l9l5- 1,245,603. Patented Nov. 6, 1917.

F/Q'Ql 5 WE C M M UNITED STATES PATENT OFFICE.

WILFRED LEWIS, 0F HAVERFORD, IENNSYLVANIA, ASSIGNOR TO THE TABOR MANU-FACTURING COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION OFPENNSYLVANIA.

VIBRATOR.

Application filed June 10, 1915. Serial No. 33,349.

To all whom it may concern:

Be it known that I, WILFRED LEWIS, a citizen of the United States ofAmerica, residing in Haverford, in the county of Montgomery, State ofPennsylvania, have in-' vented certain new and useful Improvements inVibrators, of which the following is a true and exact description,reference being had to the accompanying drawings, which form a partthereof.

My present invention relates to fluid pressure devices commonly calledvibrators such as are employed in the metal founding art to set apattern into rapid vibration relative to the mold in the pattern drawingoperation, to annul the adhesion, so to speak, between the mold andpattern without-appreciably enlarging the mold.

As practically constructed such vibrators comprise a barrel or cylinderhaving closed ends which serve as anvils to receive the impact of thehammer formed by a piston working in the cylinder or barrel, andreciprocated with great rapidity by the pressure fluid, ordinarilycompressed air, which is alternately admitted to, and permitted toexhaust from the cylinder. The piston or hammer element of such avibrator moves back and forth with great rapidity, the number of blowsstruck per minute by the hammer commonly running from eight to twentythousand, depending on the size and design of the vibrator. Inconsequence of the force and high frequency of the blows struck by thepiston, great difliculty has been experienced in preventing theseparable parts of the vibrator from workmg loose in operation, and insecuring the strength necessary to prevent rupture of the instrument.

The object of my present invention is to overcome the difiicultiesreferred to, and this I accomplish by providing a suitable resilientcushion for the metallic parts serving as the anvils receiving theimpact of the vibrator piston. The cushion material which I now considerpreferable, from a practical standpoint, is compressed cork, thoughother materials may be employed for this purpose.

The various features of novelty which characterize my invention arepointed .with articularity in the claim annexed to and orming a part ofthis specification. Fora better understanding of the invention,

Specification of Letters Patent.

out

Patented Nov. 6, 1917.

Figure 1 is a longitudinal section of a vibrator constructed inaccordance with the present invention;-and

Fig. 2 is a transverse section taken on the line 22 of Fig. 1.

In the drawings, A represents the barrel or cylinder body of thevibrator, and B the piston working therein. As shown, there are twoinlet ports A and A -leading from a common supply passage A to thecylinder space A within the member A. The barrel A is also formed withtwo sets of exhaust ports. A and A respectively. The piston B, whichisbut little shorter in length than the cylinder space, is formed withcircumferential grooves B and B which communicate through radialpassages. B with a corresponding axial passage B extending into thepiston one from each end. Extending across the ends of the cylinderspace A are washer like anvil members D and D ordinarily formed like theiston B of tempered steel. These are hel in place by ca members C andCscrewed on to the three ed ends of the cylinder body A and forming theends of the vibrator cylinder proper. As shown, the anvil members D andD are provided on their outer ends with central bosses D which registerwith central chambers C in the ca members C and G. Surrounding each ossD is a washer like cushion E of a suitable resilient compres-, siblematerial. As already stated, I consider compressed cork to be superiorto any other substance now known to me out of which to form the cushionsE. 'Each cushion which filled with lubricating material H or rather feltimpregnated with lubricating material. As shown the cap member C isformed with apertured ears C by which the vibrator may be clamped to apattern or to the pattern plate of amolding machine or the like,

In Fig. 1 the piston B occupies an intermediate neutral position Whenthe vibrator is not in operation the piston B is prevented occupyingthis intermediate neutral position by a spring F seated at its ends insockets formed in the washer D and the adjacent end of the piston B.This spring holds the piston B against the anvil member D. When thepiston B thus engages the anvil member D, the left hand end of thecylinder space A is connected to the supply passage A through port Achannel B and the corresponding radial port B and axial passage B*. Atthe same time the right hand end of the cylinder space is connected tothe exhaust ports A through the groove B and the corresponding radialport B and axial passage B ith the parts in the position just described,thepressure fluid, when supplied to the passage A moves the piston B tothe'right, and this moves the groove B out of'register with the port Aand into register with the exhaust passage A and at the same time movesthe groove 13 out of register with the exhaust passages A and intoregister with the supply port A whereupon the return movement of theanvil is brought about. This port arrangement of the apparatus and thevalve action of the piston causes the piston to reciprocate at highspeed so long as the compressed air or other pressure fluid is suppliedto the inlet passage A, as will be readily apparent to those skilled inthe art, especially as the vibrator shown difi'ers from those which havelong been in common use, only in the provisions made for cushioning theanvil. I

I have found by an extended practical use of my invention that theprovision of the cushion anvils as described markedly decreases theliability of the parts of the device working loose, and greatlydecreases the tendency of the device to rupture under the strains andstresses due to. long continued operation. At the same time, thecushioning of the anvils does not appear to materially impair or changethe efi'ectiveness of the vibrator in freeing patterns from molds, or

teases in like uses. My practical experience leads me to believe thatthe cushions formed of compressed cork or other suitable compressiblematerial, are so long lived as to be practically indestructible whenmade with sufiiciently large contact surfaces, as they readily may be. Iattribute the fact that the compressed cork cushions which I have useddo not disintegrate'or char in operation, to the fact, that the cork isporous and the fine pores contain a considerable amount of air whichactually perform a major portion of the cushioning function. Ordinarilythe vibrators are double acting as shown, but when made single acting acushioned anvil will obviously be needed at one end only of the cylinderspace.

While in accordance with the provisions of the statutes I haveillustrated and described herein the best form of my invention now knownto me it will be apparent to those skilled in the art that changes maybe made in the form of my invention Without departing from its spirit,and that some features of my invention can be used in some cases Withouta corresponding use of other features of the invention.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

A vibrator of the kind described comprising a metallic cylinder formedwith a cylinder space and with a lubricant receiving cavity smallerindiameter than, and centrally located in one end wall of said space, areciprocating piston working in said space, a movable metallic anvilmembar in said space, said anvil member being formed with a centralaperture and with an annular projection on its outer side adjacent, andin register with said cavity and a Washer of compressible resilientmaterial surrounding the annular projection of said anvil member andinterposed betweenthe body of the latter and the end wall of saidcylinder space.

WILFRED LEWIS.

